This disclosure relates to sound management.
A considerable sound problem exists in vehicles equipped with Continuously Variable Transmission (CVT), i.e., when the vehicle accelerates a constant pitch is emitted for the engine. This sound problem is more pronounced for small displacement engines, which have a lower torque, and therefore, are more likely to operate under constant RPM conditions while accelerating.
In CVT equipped vehicles, an operator may notice that at some point during an acceleration cycle, an engine RPM reaches a value that stays relatively constant. At the same time, a speed of the vehicle continues to rise. When the operator requests the vehicle to accelerate and feels the acceleration, the sound of the CVT power train provides an incorrect sound feedback, suggesting that the vehicle is not accelerating. This is not just a power train (PT) sound quality problem, but can also be a safety issue, since the operator may be tempted to further accelerate.
A similar sound problem exists in electric vehicles and hybrid vehicles running in an electric mode.